Photo-copying devices

Claim 1

A PHOTO-COPYING DEVICE COMPRISING A BASE HAVING A PAIR OF LIGHT-TIGHT CHAMBERS AT OPPOSITE ENDS THEREOF, A SPINDLE POSITIONED IN A FIRST OF SAID CHAMBERS FOR PERMITTING A ROLLED SHEET OF PHOTO-SENSITIVE PAPER TO BE UNROLLED AS IT IS WITHDRAWN FROM THE CHAMBER, A SECOND SPINDLE POSITIONED IN THE SECOND LIGHT-TIGHT CHAMBER AND A CRANK HANDLE AFFIXED THERETO FOR ROLLING UP SAID SHEET OF PHOTOSENSITIVE PAPER, A RESILIENT PAD AFFIXED TO THE UPPER SIDE OF THE BASE BETWEEN THE LIGHT-TIGHT CHAMBERS, A FLEXIBLE TRANSPARENT SHEET ATTACHED TO THE BASE, MEANS FOR HOLDING THE SHEET UNDER TENSION IN A FIRST POSITION OF THE DEVICE TO ESTABLISH A PRESSURE BETWEEN THE SHEET AND THE PAD IN ORDER TO MAINTAIN SUBSTANTIALLY UNIFORM CONTACT BETWEEN COPY MATERIALS PLACED BETWEEN THE TRANSPARENT SHEET AND THE PAD, AND A LIGHT-TIGHT CURTAIN AFFIXED TO THE BASE AND DISPOSED TO COVER THE TRANSPARENT SHEET WHEN THE PHOTOSENSITIVE PAPER IS NOT TO BE EXPOSED.